Article
Optics
Wang De-Tang, Ren Zhi-Gang, Liu Sha, Zhao Yong-Qiang, Fang Hui, Zhang Lian-Dong
Summary: The paper proposes a non-uniformity correction algorithm based on polarization redundancy estimation, which achieves correction effect of the entire focal plane through statistical information and difference analysis, and eventually verifies the effectiveness of the algorithm through experiments.
JOURNAL OF INFRARED AND MILLIMETER WAVES
(2021)
Article
Environmental Sciences
Bing Wu, Chengyu Liu, Rui Xu, Zhiping He, Bin Liu, Wangli Chen, Qing Zhang
Summary: This paper proposes a novel target-based non-uniformity self-correction method for infrared push-broom hyperspectral images. The method is validated and evaluated using laboratory and in-orbit hyperspectral data, demonstrating its feasibility and effectiveness. It can be used as a non-uniformity correction process for the MMS and similar hyperspectral imagers.
Article
Optics
Yi He, Tingwen Xing, Wumei Lin, Zhijie Liao, Weijing Liu
Summary: A method for correcting the illumination uniformity error in lithography optical system is proposed, which includes establishing a mathematical model based on linear invariant system and convolution principle, and designing a uniformity correction device with bidirectional calculation characteristics. The measurement results validate the correctness and effectiveness of the correcting method.
Article
Optics
Hongfei Song, Kehang Zhang, Wen Tan, Fei Guo, Xinren Zhang, Wenxiao Cao
Summary: This paper proposes a stripe non-uniformity correction algorithm based on scene-adaptive nonlinear filtering. The algorithm effectively removes stripe non-uniformity and noise in infrared focal plane array (IFPA) imaging, while protecting image edges.
CURRENT OPTICS AND PHOTONICS
(2023)
Article
Optics
Hongfei Song, Kehang Zhang, Wen Tan, Fei Guo, Xinren Zhang, Wenxiao Cao
Summary: This paper proposes a stripe non-uniformity correction algorithm based on scene-adaptive nonlinear filtering, which effectively removes stripe non-uniformity in infrared focal plane array (IFPA) imaging and achieves high-quality images.
CURRENT OPTICS AND PHOTONICS
(2023)
Article
Computer Science, Information Systems
Jun Dong Yeo, DooHyung Woo
Summary: This study presents a new readout integrated circuit and non-uniformity correction method to ensure low non-uniformity in a bolometer array over a wide operating temperature range. The proposed method minimizes circuit and memory requirements for signal processing, making it suitable for compact and power-efficient portable infrared cameras.
Article
Optics
Yitong Li, Ning Liu, Ji Xu
Summary: This paper introduces an infrared scene-based non-uniformity correction method based on deep learning technology, which addresses the limitations of traditional correction methods in parameter convergence and correction failure, improving the adaptability and accuracy of correction.
Article
Chemistry, Analytical
Mingqing Li, Yuqing Wang, Haijiang Sun
Summary: In this paper, a method for the correction of non-uniformity in single-frame infrared images is proposed based on noise separation in the wavelet domain. Experimental results demonstrate that the proposed method achieves optimal levels among compared methods and significantly reduces the non-uniformity index on real-world test image sequences.
Article
Computer Science, Interdisciplinary Applications
M. Kavousanakis, N. Cheimarios, G. Kokkoris, A. G. Boudouvis
Summary: This study examines the effect of self-sustained periodic flows on the thickness non-uniformity of deposited films in a CVD reactor. The results show that the films produced under this condition are highly non-uniform and not suitable for practical applications.
COMPUTERS & CHEMICAL ENGINEERING
(2022)
Article
Computer Science, Interdisciplinary Applications
Feifei Wang, Yingqiu Zhu, Danyang Huang, Haobo Qi, Hansheng Wang
Summary: One-shot-type estimators are commonly used in distributed statistical analysis, but their efficiency depends on conditions like uniformity and randomness. A novel OSUP method is proposed to address violations of these conditions, utilizing pilot estimates and one-step updating to improve efficiency. Experimental studies show that the OSUP estimator performs well in finite sample scenarios.
COMPUTATIONAL STATISTICS & DATA ANALYSIS
(2021)
Article
Automation & Control Systems
Chen Mo, Yongchao Xu, Shijian Yuan
Summary: A hydroforming method using a circular 5A06 aluminum alloy plate with a radial differential thickness and a flexible polyurethane auxiliary plate was proposed for eliminating annular welding seams in welding structures. Deep drawing experiments were conducted to analyze the thickness and strain of drawn specimens with different thickness ratios under different hydraulic pressure. Hydroforming effectively improved the formability of 5A06 aluminum alloy plates with differential thickness, achieving integrated semi-ellipsoid shells with varying thickness ratios under specific hydraulic pressure.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2023)
Article
Optics
Kyuseok Kim, Youngjin Lee
Summary: This study investigated the application of a non-uniformity correction framework in the DBT system to improve image visibility, and demonstrated its effectiveness through simulation and experimental validation. The proposed framework successfully corrected non-uniformity at low X-ray exposure condition, showing promising potential for efficient DBT imaging performance.
Article
Physics, Multidisciplinary
Maxime A. Tremblay, Nicolas Delfosse, Michael E. Beverland
Summary: Quantum low density parity check (LDPC) codes offer a potential solution for building low-overhead fault-tolerant quantum computers. However, their general lack of geometric constraints can lead to complex layouts and performance degradation. To address this issue, we propose a 2D layout for quantum LDPC codes by decomposing their Tanner graphs into planar layers. Our findings demonstrate that, under certain conditions, we can achieve low circuit-noise threshold and reduce the number of required physical qubits.
PHYSICAL REVIEW LETTERS
(2022)
Article
Polymer Science
Shaofei Jiang, Yuansong Zhang, Haowei Ma, Xiaoqiang Zha, Xiang Peng, Jiquan Li, Chunfu Lu
Summary: This study experimentally investigated the replication uniformity of microstructures and found that the cavity thickness and process parameters have significant influence on the uniformity. The experimental results provide important data on how to improve the replication uniformity of parts with microstructure arrays.
Article
Materials Science, Ceramics
Sun-Young Park, Minh-Tan Ha, Kyoung-Ho Kim, Le Van Lich, Yun-Ji Shin, Seong-Min Jeong, Se-Hun Kwon, Si-Young Bae
Summary: This article presents a method for growing smooth surface and high thickness uniformity corundum-structured (alpha-) gallium oxide (Ga2O3) crystalline thin films on sapphire substrates using vertical hot-wall mist chemical vapor deposition (CVD). By tuning the growth variables and microdroplet diameter, optimal surface morphology and growth rate can be achieved. The even flow of mist in the vertical furnace ensures high thickness uniformity of the Ga2O3 epitaxial layer on large-scale substrates.
CERAMICS INTERNATIONAL
(2022)
Article
Clinical Neurology
Ju Lynn Ong, S. Azrin Jamaluddin, Jesisca Tandi, Nicholas I. Y. N. Chee, Ruth L. F. Leong, Reto Huber, June C. Lo, Michael W. L. Chee
Summary: The improvement of cognitive abilities during adolescence is associated with brain maturation, including cortical thinning and reduced sleep slow wave activity. This study found that age-related improvements in processing speed and nonverbal intelligence are mediated by reductions in cortical thickness and sleep slow wave activity. These findings suggest that cognitive development is closely related to brain structure and sleep.
Article
Clinical Neurology
Stijn A. A. Massar, Alyssa S. C. Ng, Chun Siong Soon, Ju Lynn Ong, Xin Yu Chua, Nicholas I. Y. N. Chee, Tih Shih Lee, Michael W. L. Chee
Summary: This study examined the changes in sleep, physical activity, and wellbeing during the COVID-19 lockdowns and reopening. The findings showed that upon reopening, there were earlier sleep timings, increased physical activity, but also higher self-rated stress and poorer evening mood ratings. The study also found that work/study arrangements and smartphone usage patterns influenced these changes.
Article
Clinical Neurology
June Chi-Yan Lo, Tiffany B. Koa, Ju Lynn Ong, Joshua J. Gooley, Michael W. L. Chee
Summary: In this study, the deterioration of vigilance with increasing time-on-task (ToT) during recurrent sleep restriction was characterized. Afternoon napping was found to be effective in ameliorating ToT-related deficits.
Article
Clinical Neurology
Hosein Aghayan Golkashani, Ruth L. F. Leong, Shohreh Ghorbani, Ju Lynn Ong, Guillen Fernandez, Michael W. L. Chee
Summary: This study investigates the effects of sleep and having a schema on initial learning. The results suggest that having a schema and regular nap opportunities can enhance learning and memory recall, and this effect is associated with fast spindle density.
Article
Clinical Neurology
Shohreh Ghorbani, Hosein Aghayan Golkashani, Nicholas I. Y. N. Chee, Teck Boon Teo, Andrew Roshan Dicom, Gizem Yilmaz, Ruth L. F. Leong, Ju Lynn Ong, Michael W. L. Chee
Summary: This study evaluated the benefits of applying an improved sleep detection and staging algorithm to wearable data collected from older generation hardware. The results showed that the new algorithm performed better than the existing algorithm in terms of sleep classification accuracy and specificity, and it could accurately assess sleep characteristics. Age and gender had some impact on the results, and collecting raw data allowed for future advancements in algorithm development or sleep physiology.
NATURE AND SCIENCE OF SLEEP
(2022)
Review
Clinical Neurology
Ruth L. F. Leong, June C. Lo, Michael W. L. Chee
Summary: Research shows that napping has cognitive benefits, especially in terms of memory, vigilance, processing speed, and executive function. These effects are not influenced by age, nap duration, or habitual napping.
SLEEP MEDICINE REVIEWS
(2022)
Article
Clinical Neurology
Ju Lynn Ong, Stijn A. A. Massar, TeYang Lau, Ben K. L. Ng, Lit Fai Chan, Daphne Koek, Karen Cheong, Michael W. L. Chee
Summary: This study evaluated the efficacy of a digitally delivered, small and scalable incentive-based intervention program on sleep and wellbeing in short-sleeping, working adults. The results showed that the program achieved some positive effects on improving sleep and short-term sleep extension.
Editorial Material
Clinical Neurology
Michael W. L. Chee, Thomas Svensson
Article
Clinical Neurology
Shuo Qin, Ruth L. F. Leong, Ju Lynn Ong, Michael W. L. Chee
Summary: This meta-analysis examined associations between objectively measured sleep parameters and cognitive performance in healthy older adults. It found that both sleep macrostructure and microstructure were related to cognitive function. The relationship between sleep and cognition was moderated by age, education, and percentage of female participants. This study highlights the importance of objective sleep measures in understanding the relationship between sleep and cognition in healthy older adults.
SLEEP MEDICINE REVIEWS
(2023)
Article
Clinical Neurology
Ruth L. F. Leong, TeYang Lau, Andrew R. Dicom, Teck Boon Teo, Ju Lynn Ong, Michael W. L. Chee
Summary: The study aimed to investigate the effects of mid-afternoon naps on memory encoding, vigilance, speed of processing, mood, and sleepiness. Naps of durations ranging from 10 to 60 minutes were found to improve positive mood and alleviate self-reported sleepiness up to 240 minutes post-nap. Only the 30-minute nap showed benefits for memory encoding, while improvements in vigilance were moderate and no benefits for speed of processing were observed. Sleep inertia was observed for naps of 30 to 60 minutes but resolved within 30 minutes after waking.
Editorial Material
Neurosciences
Michael W. L. Chee, Adrian R. Willoughby
Summary: Large-scale, global studies on sleep and its relationship with cognitive performance are rare. A recent study using a video game found that among 54-70 year old participants, optimal wayfinding performance was associated with a self-reported sleep duration of 7 hours. The study also found that geography and/or culture significantly influenced sleep duration, which warrants further investigation.
TRENDS IN NEUROSCIENCES
(2023)
Article
Chemistry, Analytical
Gizem Yilmaz, Xingyu Lyu, Ju Lynn Ong, Lieng Hsi Ling, Thomas Penzel, B. T. Thomas Yeo, Michael W. L. Chee
Summary: This study utilized machine learning to predict nocturnal blood pressure using single-channel fingertip plethysmography. The results demonstrated the accuracy of the predictions, highlighting the potential for a cuffless method to continuously monitor blood pressure during sleep.
Article
Clinical Neurology
Gizem Yilmaz, Ju Lynn Ong, Lieng-Hsi Ling, Michael W. L. Chee
Summary: The study examines the changes in PPG waveform during sleep and its correlation with arterial elasticity and age effects. It finds that deeper sleep is associated with lower arterial stiffness and that age has a significant impact on these changes.
Article
Clinical Neurology
Adrian R. Willoughby, Iman Alikhani, Mari Karsikas, Xin Yu Chua, Michael W. L. Chee
Summary: Based on an analysis of 50 million nights of sleep data from 220,000 wearable device users in 35 countries, this study found that Asian countries have shorter and later sleep, lower sleep efficiency, and shorter weekend sleep extension compared to Europe and the USA. The study also suggests that cultural differences related to work may influence the variability in sleep patterns worldwide.
Article
Clinical Neurology
Alyssa S. C. Ng, Stijn A. A. Massar, Bei Bei, Michael W. L. Chee
Summary: This study investigated the impact of sleep duration, timing, and efficiency on mood, motivation, and sleepiness levels. The results showed that longer sleep duration was associated with better mood, higher motivation, and lower sleepiness after waking, but the effects did not extend to the next day. Higher sleep duration variability was associated with poorer mood and lower motivation after waking. The findings suggest that sleep duration and variability have temporal circumscriptions on individuals' daily readiness.
Article
Neurosciences
Jose Sanchez-Bornot, Roberto C. Sotero, J. A. Scott Kelso, Ozguer Simsek, Damien Coyle
Summary: This study proposes a multi-penalized state-space model for analyzing unobserved dynamics, using a data-driven regularization method. Novel algorithms are developed to solve the model, and a cross-validation method is introduced to evaluate regularization parameters. The effectiveness of this method is validated through simulations and real data analysis, enabling a more accurate exploration of cognitive brain functions.
